interface Person1 {
    "id": string,
    "gender": string,
}

interface Person2 {
    "id": string,
    "gender": string,
    "age": number
}

// 可选
interface Person {
    "id": string,
    "gender": string,
    "age"?: number
}

let p1:Person = {
    "id":"abc",
    "gender":"M"
}

let p2:Person = {
    "id":"abc",
    "gender":"M",
    "age":20
}

console.log(p1)
console.log(p2);


